Equipment/Overflows - 03/25/2006 Hey,
<Hello> How are you doing? Anyway, I have a 55 gallon tank and I
want to build a sump so I bought this over flow box
https://www82.safesecureweb.com/webaquatics/Merchant2/merchant.mvc?Screen=PROD&Product_Code=ACO75&Category_Code=WDF
(if it doesn't appear it's at www.webaquatics.com in the
filters, wet/dry filters then titled "Overflow Box for 75/125
Filter (Pro Clear)"). I was thinking of what pump I
should get for this overflow, maybe a Mag 5? or a Rio 12HF? and if
those two aren't the way to go then what pump do you
suggest? Thanks for your time. <I'd ask that question
to Web Aquatics or Pro Clear. There is not enough info
present in the ad to suggest a pump size. James (Salty
Dog)> Akbar

Set Up/Sump/Drain Size - 03/12/2006 Hi....<Hello
Mike.> Thanks for your time. Fantastic web
site. "Before" doing my homework I
bought an all-glass 54 gallon corner tank. I thought that
the 1 1'4" predrilled drain would be enough for this tank
draining about 600gph but after reading the fine print I found out that
in the corner tanks the flow is only 400gph. I'm
considering using the predrilled 3/4" return hole as another drain
and plumbing the return over the top of the tank. I'm
just not sure if the two different sized drains will be a problem and
if the skimmer box will be able to handle this additional flow of water
without backing up. Any quick thoughts would be
appreciated. <Mike, the 1 1/4 drain is more than enough
for a 600 gph flow. Don't know where the "fine
print" came from. James (Salty Dog)> <<James,
after the diameter of the bulkhead is considered, the inside diameter
of this through-put will likely be less than an inch... RMF>>
Thanks for your time <You're welcome.> Mike

Re: Set Up/Sump/Drain Size - 03/12/2006 -
03/13/2006 Are you sure, Bob? Seems like all the bulkhead fittings
I've used will allow the entire ID of the pipe to be of use, that
is once you slip the PVC pipe in, and look into it, you cannot see any
restrictions caused by the bulkhead fitting, that is, the lip on the
bulkhead is the same size as the thickness of the pipe. In
using the drain size calculator, for a 600gph flow rate, a minimum pipe
diameter would be 1.01 inches. The results do not specify ID
size so I'm assuming it is the actual pipe diameter which is how
pipe is measured anyway (I'm sure you know). A 1 1/4
pipe has a ID of 1 1/4 inches. If you believe I am
wrong...my apologies. James <Am pretty sure the writer is referring
to the OD of the hole cut in the tank... the throat of the bulkhead
takes up space/diameter. B>

Two Pumps on One Bulkhead? - 03/10/06 Hi Crew, <<Hi
Tom>> Yet more questions for the pros as I plan a new 130G reef
tank. <<Thanks...EricR here...not so much a "pro" as
just wanting/willing to assist...offer up my perspective...>> I
want to put a bulkhead in the rear panel of the tank, about 6-8"
below the waterline, that will feed a circulation loop into a couple of
SeaSwirl returns. <<A great idea.>> I need that bulkhead to
feed two external pumps, on closed loop, with a combined pull of about
2000GPH. <<Mmm...ok...this 'could' work, though I would
prefer to use a separate bulkhead (1") per pump. These
"balancing acts" between two pumps can be
problematic.>> I know a 1.5" bulkhead in an overflow is
rated around 1600GPH with just a gravity feed, <<And not without
problems.>> but do you think a 1.5" bulkhead will adequately
feed 2000GPH to a couple of pumps pulling on it? <<Should do,
yes...different hydro-dynamics at play here. Most any pump
can/will "pull" its flow rate through its rated intake size
(not to be confused with "sucking,", the pump must still be
properly installed below water level so it is
"flooded."). Is this making sense?>> In
other words, what is the largest pump you know of that comfortably
works with a 1.5" intake bulkhead feeding a closed loop?
<<Any of them with an intake port up to 1 1/2" in
size.>> A couple of local guys tell me it should be OK, but I
would sure like to hear your view. <<Honestly, I don't like
the idea...but that's only my/one opinion. I would
prefer to match a single pump per bulkhead rather than guessing at how
two pumps will perform on one bulkhead, whether one will
"starve" the other, etc..>> I'm trying to halve the
leak potential, and plumbing hanging off the back of the tank, by going
with a single bulkhead to feed the pumps. <<Understood, and
I'm not saying it won't work...but I do feel it is
"false" economy.>> I'd also like to avoid 2"
bulkhead and pipe (it's huge!) if I can. I'd like to
run 1.5" PVC from the bulkhead to just above the pumps, then
"T" to a couple of 1" pipes into these pumps that have
3/4" intake fittings. <<In theory, the 1 1/2" bulkhead
should provide enough water to feed two 3/4" pump
intakes. Might I suggest that you give this a try and let it
run for a day/couple days under close observation to see how it
performs...but leave your options open to add a second bulkhead if
necessary. Let me know how it works out. Regards,
EricR>> Thanks, Tom Two Pumps on One Bulkhead? II -
03/10/06 Eric, the tank builder cut the hole for a 2" bulkhead
while I was debating...takes care of that dilemma. <<Mmm...reckon
so...>> So the two pumps will still share a single bulkhead feed
but at least it will be a very large one. <<Indeed!>>
Related question, what's the absolute best way for me to insure a
leak proof & relatively permanent seal on that 2" bulkhead?
Silicone sealant on the gasket & threads? I don't
plan on ever having to remove it, but I do have to place it against a
wall. <<Silicone is the way to go, yes. No need to
seal the threads, just run a smear/small bead around the perimeter of
the hole under the gasket and tighten...let the silicone cure before
adding water. The silicone won't "stick" to
the bulkhead fitting, facilitating removal should it ever be necessary,
but it will "seat" the gasket nicely providing the leak-proof
seal you desire.>> Thanks, Tom <<Always a pleasure,
EricR>> <Mmm, better to not have centrifugal pumps
"pulling against each other, or other low pressure... RMF>
Plumbing an Overflow in an Established Aquarium - 03/09/2006
Hello WWM crew, <Hey Joe...(sorry, one of my favorite songs:)> I
have had my aquarium for about a year. It is a 55 gallon
FOWLR. I want to make the jump to making it a reef aquarium.
<And into the rabbit hole we go.> For the last 8 months I have
used a DIY Ecosystem style sump with miracle mud and Caulerpa algae.
When I installed the sump I made a DIY overflow box. So far I have been
lucky with the overflow box and haven't had any breakdowns.
<We're safe...but for how long? (The Kids in the Hall)> In
fact, the syphon hasn't been broken once since I installed
it. But more and more I want to get away from it. I want to
be able to cover the tank better because I have lost a couple fish that
jumped out. Also I am constantly nervous that it will malfunction.
<Rightly so.> Every once in a while I hear the noise from my
bedroom and I can't sleep for worrying (this happens rarely but
when it does it is quite nerve racking). I was wondering if it would be
too difficult to have the tank drilled now, what it would entail, and
the impact it would have on my livestock. <And back to the song
"Hey Joe, where you gonna run to now? Where you gonna go?"
Fitting eh? Drilling with all intact is not going to work. You would
have to break it all down for this. My suggestion? If you can't
drill it, don't sump it. You don't have to use a sump. Many
hang on refugium type additions that can serve your desires
here.> Thank You, Joe Lace <You're welcome. Sorry
for my horrid singing (and I was). - Josh> CPR BakPak to overflow
conversion 03/9/06 Hello, <Hi Craig.> I am
wondering what your thoughts are on plumbing my CPR BakPak to a new
refugium I would like to add to my tank. I am thinking I can
plumb a stand pipe though the bottom of the BakPak which would flow to
a newly placed refugium tank and plumb a return line back into the
display tank. Have you heard of anyone else doing this? Are there any
obvious reasons why I would not want to do this? It seems to me that I
can save a good chunk of money by using what I already have laying
around. <Seems to me like very little water would be processed
through the skimmer itself rendering the skimmer close to
useless. Other problem is what if your return
pump in the refugium quits...how much water are we going to pump into
the refugium before the CPR pump starts cavitating from lack of
water. I'd think about it my friend. James
(Salty Dog)> Thank you! -Craig Overflow Noise - 03/04/06
Greetings crew- <<Hello Penny>> I have emailed in the past,
and received a very informative response, so here I go again.
<<Hopefully I will live up to your expectations.>> I have
read FAQs until my eyes hurt; posted questions on all the forums
I'm a member of; asked friends...done all I could before I decided
to bug you guys. <<Not "bugging" us,
really.>> Here's my problem: the water overflowing
from my main tank into my sump/fuge is very very loud. <<A common
problem.>> I finally got all the other noises under control and I
just can't figure out how to get this one down.
<<Let's see if I can help.>> My setup: I
have a 105 gallon Oceanic (does this make a difference?) with a single
overflow. <<Depends...how much water are you trying to push
through this?>> The over flow uses a 1.5"
tube. The water flows through the Durso standpipe setup that
was provided with the tank into the sump. <<Ah yes, the standpipe
is 1.5" but I believe the bulkhead/drain are only 1".>>
Here's where the noise happens. It sounds like Niagara
Falls. Then it flows into the 'fuge section, and finally
into the return section. We were using a CA3000 pump, but at
1000gph, were told this was too much. <<Indeed>> We
replaced it with a Mag7, which solved the problem we were having with
the flushing/burping sound. <<Mmm, still might be too
much...depending on head height, you may find a Mag5 will solve your
problem.>> The water is returned to the tank through a .75"
tube/pipe. (All 'soft' plumbing). If you
need more information on my setup, please let me know. Any
thoughts on this? <<Plenty...I think you are still trying to push
too much water through that single 1" overflow, I recommend you
try to turn no more than 300/350 gph through your
sump. Believe me, it will make a difference. If
you need more flow than this in your tank; and you do, use a larger
pump to plumb a closed-loop for the system.>> Thanks in advance
for your help! -Penny <<Regards, EricR>> Acrylic
repair 3/4/06 Hello Bob, <Tony> I would like your
advice on repair of acrylic tank. I have never owned an
acrylic tank before. Just purchased an 180 gallon acrylic
fish tank. The previous owner made 3 holes for pipes used in an
overflow sump. ( mostly for salt water). I need to plug up the holes to
house my Arowana. Any advise on how to plug up these holes.. Any
suggestion would be helpful.. Thanks Tony <I would make these
"temporary"... rather than affix the mentioned cover pieces
with solvent (as the rest of the seams)... By using Silastic (100%
Silicone Sealant) and "squares" of appropriately thick
acrylic (look in the "used/scrap bin" of a plastics
dealer/fabricator), over-lapping the holes by an inch or more, making a
thin bead, smooshing the covers onto the inside of the tank, over the
holes, taping in place for a day or so... Bob Fenner>

Overflow Covers? 3/3/06 Hello, I have a custom
made Oceanic glass tank. Approximate dimensions are
63"L x 28"W x 50"H. <! Wowzah... four plus feet tall?
Mmm, maybe the stated W and H are mixed...> Do you know are there
any companies or products out there that make covers for the overflow
box. <I would check with the manufacturer here... or resolve to make
these yourself (not hard to do...> In a tank this large I am having
a hard time adequately covering or hiding the box. Any
suggestions? <Mmm, large stacked piles of rock decor... fashioning
faux material to fit over/around... is this a marine system?> Do you
recommend gluing any live rock to the box? <Good question, and
no...> I really don't know where to go for
ideas. Thanks again for a great site and all of the great
info. You guys rock!!! Thanks, Skip <Check with Oceanic
here for their suggestions, and please relate what they state back to
us for sharing. Thank you, Bob Fenner>

Re: Overflow Covers? 3/4/06 Bob, Thanks for the
reply. The dimensions of the tank are correct. It
is closer to a square if you can imagines that look. <Ooof, I can.
Glad I wasn't there for moving day!> Anyway, I
contacted Oceanic who recommended using epoxy to attach the rock to the
cover. Why don't you like this idea? I have been given
this suggestion by several dealers now and am always curious to hear
the other argument. <Mainly the lack of ease of changing this... not
easy, practical to "bust off" later> Oceanic did give me
the name of an individual in the Dallas area that does them (but it is
quite pricey). They also recommended that I call a company
called Aquarium Design Group in the Houston area. After some
more searching on the web I did find that brand new this month, Living
Color www.livingcolor.com, launched a new line of pre-formed overflow
covers. <Oh?> 5 different styles to match your
setup. Actually pretty cool. <Sounds very good> I did
speak with them and they can make customized versions, although the
price was definitely getting up there. I think I would
rather put the money into other things for the tank. Anyway
hopes this helps. Will be interested to hear your answer on epoxy use
on the overflow. Thanks again for all of the info. Take Care, Skip
<Though it's a bunch of stacking... am still a fan of piled
rock. Cheers, Bob Fenner> Re: Tank/Sump/Plumbing
3/3/06 James, thanks for the response and I apologize for the poor
grammar. After looking at the sump diagram on OzReef.org, I
have a few final questions about the sump: I'm going to use two
bulkheads for my return lines, using LocLine and flare nozzles to
replace my powerheads. Should I connect each return to a
separate pump, or would I be better off using one powerful pump to
power both returns? <I like the idea of two separate
pumps. The "T" connector will reduce the flow of
both pumps close to 10%.> If one pump is used, how powerful should
it be and will I get equal pressure in both returns (using a t/y
connector)? (mag drive, 55 gallon, 4 foot head max). <Here is a link
to some flow calculators so you can select the correct
pump. http://www.reefcentral.com/calc/hlc2.php> How large
should my drain and return bulkheads be for this size of an aquarium?
I'm assuming the return bulkheads should be smaller in diameter
than the drain? Would it be safer to install two drains, or would I be
alright with one large drain? <One drain will work and pipe sizes
can also be determined in the above link. Look on the left
sidebar for different calculators.> Do issues generally arise in the
ability of the pumps to drain the sump as fast as the drain line fills
it, or in the ability of the drain lines to fill the sump fast enough
to keep the pump(s) from running dry? I want to use vinyl tubing
instead of PVC to connect the sump and the display tank. <Obviously
we don't want a pump that is capable of pumping more water than the
sump can receive. This info can be found on the link
also.> Do the return and drain bulkheads have to be on an equal
plane against the back of the tank? I plan to place them high up on the
tank. <I would put them on a equal plane. You have to
protect yourself in the event of a power failure so you don't
overflow your sump and putting the drains/returns too low will cause
this. You may want to consider check valves on the returns
to prevent a siphon should this occur, but if your sump is sized
properly this shouldn't happen.> Thank you once
again. Sorry about the relentless e-mails, but your help is
and has been invaluable to me. <Understand. James (Salty
Dog)>

Standpipe/Bulkhead Size 2/18/06 Hello, <Hi Gabe>
I asked you guys some questions a couple of days ago but received a
puzzling reply that left me without answers. <Sorry, that was my
doing. I could have swore I answered that
query.> I have included the original message and your
reply below. I am not sure if this reply means that I should find the
answers by searching previously "answered" queries, or that
James felt that someone else had already answered this particular
query. I am pushed for time on this installation and have already
ordered the 2" bulkheads due to space and price. If you
felt as though I did not research this sufficiently I would like to
explain myself. I understand my desired flow requires a drain/bulkhead
between 2.26" and 2.61" using the calculator at
reefcentral.com (which reference I found at WWM.com). I also found that
recommendations made by much of the WWM crew on drain/bulkhead sizes
seemed to be higher (many times double) than what the calculator
provides (I am not sure, but the calculator may provide an
"exact" size without any tolerances). <Believe you are
correct here.> I also could not find a query on this subject that
had desired flow rates as large as mine. Furthermore, there have been
some suggestions to increase standpipe sizes to reduce noise levels,
but I have not found whether a grossly oversized drain could increase
the noise level. I requested your preference or opinion on bulkhead
size due to the noise factor and the vagueness of information presented
on sizes vs. flow requirements. I did find sufficient information to
promote the vent I was asking about by further searching WWM (shame on
me). I do hope I have not offended you guys as it is prudent to have
such a knowledgeable group on my side. <Two 2" lines should do
the trick. Some people will go with a Durso Standpipe to
help eliminate noise. You can search/read this subject on
the WWM.> Thanks, <You're welcome and sorry for the mix
up. James (Salty Dog)> Gabriel Clams and Overflow box
question? 2/17/06 Good morning to you-
I love this site and have been using it
faithfully for a year. But alas... I now need to
ask a few questions. I have had a 38 gal. tank for over a
year. I am now getting ready to build a 135 gal. 72L x 24W x
18H w/ a plenum and 3 in. LS, 155 lb. LR, 2000 gal. an hour
filtration. I have been reading all the articles on Clams
and Lighting in reference to water depth, among others. But
I am not sure I can do what I am thinking (I may have missed
something). I would like to know if w/ a 520w Compact light
(6700K/10000k, 420/460nm) in 14 in. of water depth if a
Tridacna Crocea would be happy and healthy or would I need to still
have a MH? <Should work> Next... I
am planning on putting the skimmer box in my tank like in Anthony's
diagram. I am putting in 4 bulkheads 1.5 in. ea., the box
will be 48 in.'s long centered. I want to leave the
sides open for water flow from the manifold around the
top. Is this enough bulkheads for the 2000 gal. rate of flow
I want to get? <Should be, yes... If it were me/mine, I'd make
two (the outside ones), 2" ID, put the bottoms near the same level
as the 1 1/2"s> And will I get my flow rate if I use y
connecters and plumb 2 an 2 together or should they be plumbed
separately for better flow? <Can be linked together... need (likely)
to be aspirated to speed flow, reduce noise and
"bubbliness"> Thank You for your time-Deanna- <And you
for your sharing. Bob Fenner>

Keeping Peppermint shrimp out of overflow and to sump -
02/16/2006 Good day, Cant get enough of this website and I am
inspired by all of your generosity with your time and expertise.
Outstanding! I read the peppermint pages on WetWebMedia and did not see
this question. Background: When adding peppermint shrimp to
the display, they seem to find there way to the overflow box and go
down the standpipe into the sump. I want to keep them in the
display to combat Aiptasia (until I get my excess nutrients under
control-working on it). On another site, I asked and someone
suggested counted cross-stitch plastic sheets from craft store cut to
size to keep them from the overflow. <One choice. Some sort of
chemically inert screening> Well, it works great at
keeping the peppermints out of the overflow and in the display, but now
an oil slick is on top of the water of the display as the counted
cross-stitch material is apparently keeping the oily stuff from getting
into the overflow and down to the sump to skim, probably due to surface
tension. <Ah, yes... perhaps a larger mesh material> I live life
dangerously only have one overflow on this display by the way.
<Heeee!> So, the question is: is there a better way to keep the
peppermints in a display and out of the overflow without obstructing
the surface oily from draining into the overflow? Sean Missey <The
screening/sieving is the easiest approach here. Try something of a
bigger "draw". Bob Fenner>

About overflows pre-made... this time in an Oceanic product
question - 2/4/2006 Hello folks! <Peter> I just emailed
Oceanic to inquire about the capacity of my 74gal bowfront reef ready
tank. I have heard that it is 1200gpm but I assume this is
under siphon (which I don't want to do because of noise). <And
otherwise ideal conditions... which you/one should not rely on. These
3/4" diameter holes are inadequate... They will change... likely
soon... enough lawsuits, complaints> I'm considering
converting the Â¾' return hole in the overflow to a
second drain hole to increase the capacity. <Good idea... not too
close to the existing...> Then I would just plumb the pump return
behind the tank and up and over the edge (with a siphon
break). Any reason why this wouldn't work?
<Mmm, nope> Also, to what would you guess the capacity would be
increased (would give it a 1' and a Â¾' drain).
<Would make this 1 1/2"... cutting over the existing...>
Would I need to cut the weir slots larger to accommodate
the larger flow? <A good idea... or cut down the height a bit...>
Thanks again for all of your help. Peter <Welcome. Bob
Fenner> Re: overflow question 02-05-06 Bob, thanks for
the quick response. One point of clarification...you mention
making it 1 1/2" and cutting over the existing
hole. From my understanding, the bottom glass is
tempered. This can't be re-drilled, can it? I've
drilled holes in non tempered glass quite a few times... Thanks, Peter
<Is an issue... am given to understand that there is technology for
cutting through nowadays (have never had success with myself), but if I
were doing so here, I would likely abandon the one present hole and
drill the larger through the back. Cheers, Bob Fenner> Durso
Standpipe in an external (hang on) overflow box 1/31/06
Hi, <Howdy> I have a 1 1/4 DIY Durso standpipe in an hang on
overflow box. I purchased the overflow box from my
LFS. The box did not lose siphon in a simulated power outage
before I installed the Durso, but now it does. <Yikes, or
potential yikes> The water is siphoned from the inside
chamber too fast and siphon breaks. <Yep> I have
tried to extend the U tube way below the intake from the Durso, but to
no avail. I can't even get the U tube to hold siphon with the power
off. It seems there isn't proper equilibrium between the
inside and outside boxes. Any advice is appreciated, Thanks! <...
Well, there are plumbing arrangements that can be fashioned as a
work-around repair here, but they require a bunch of space... more than
you likely have. There are other solutions... that call for something
other than the Durso you have situated here... and these are posted...
you guessed (!) on WWM. Bob Fenner> - Setting Up a Durso Standpipe -
Hello, I went yesterday and bought all the parts for the Durso
standpipes. I have a 1" bulkhead and got all the parts according
to the instructions. Problem, I just assumed these items would fit into
my overflow, they didn't. I think I might be able to get the
1" PVC, street elbow, tee to fit inside, but the 1-1/4" will
not fit for sure. <Ok.> I read on the website that
using 1" PVC is not effective, my tank is roughly 60
gallons. <One inch should work... given the fact that you
probably won't have nutty recirculation on a tank of this size...
would certainly experiment - glue the T-fitting and street elbow
together and just press fit on top of the stand pipe... see how that
works for you.> Any suggestions on reducing the noise?
<Give this a try first and see how things go... if your tank is
still noisy, do read through the plumbing FAQs... I've posted a
couple of different solutions there.> Thanks, Rajiv
"Mickey" R. <Cheers, J -

Overflow Configuration - 01/23/06 My tank capacity
is around 970L. For return to the sump I have a corner
overflow, with two drilled holes. The height of the return
pipe has about 4 in. of stick-up from the bottom. When I
first fired up the tank, the noise of the water flowing into this
chamber was unbelievable. <<I'm sure>> The guy who
built the tank filled this chamber with the same plastic balls used in
the wet and dry filter. This has made a big difference.
<<This is a common method for reducing noise with bottom filled
tanks, but many folks have found the use of a standpipe (like the one
described here: http://www.dursostandpipes.com/)
to be quieter, and also provide additional benefit such as draining
less water to the sump in the event of a power outage.>> On the
outlet flow to my sump, instead of the flow being fed direct from 1
outlet, I have placed a PVC pipe, with the ends blanked, across the
width of the sump, and drilled holes, so the flow is spread across the
filter media. Your thoughts would be appreciated.
<<Not sure I completely understand your layout/what you mean when
you say "across the filter media," but I think this
configuration could be unnecessary if not unwanted. Ideally
water pulled from your tank would feed in to a "skimmer
chamber" in your sump to be picked up and processed by your
skimmer (assuming you have one).>> Alan <<Regards,
EricR>> Re: Overflow Configuration II - 01/26/06 Please
advise I am correct here. I can remove all the 3 different
items I have in the first chamber, and place the skimmer there to
receive the raw tank water. The water would then flow over
the top in-to chamber 2 passing through the Poly Filter and
Carbon. And then to the last chamber for return.
<<Correct, but understand I'm basing my opinion solely on
generalities and the small amount of info you have
provided. Other factors to determine your decisions are what
type of setup you have, other/supplemental filtration methods,
etc..>> I do not know what you mean by a filter sock and where to
place this item. <<Essentially, this is a filter bag placed over
the end of the overflow line to the sump. A search re on the
net/this site will yield more info.>> If I leave the setup as it
is where best would it be to place the carbon and Poly Filter.
<<Somewhere where water will flow over/through the media.>>
Please note in the main tank I have no live rock only crushed coral on
the base. Regards Alan <<Looks like you need to do some
research/reading. Let me get you started here: http://www.wetwebmedia.com/marine/setup/filtration/marineFiltr.htm
and do follow the indices in blue at the top of the page as
well. Regards, EricR>> Re: Overflow Configuration
III - 01/28/06 Thank you for all the help you have provided
regarding this subject. <<My pleasure>> I have one last
thing to ask you. <<Ok>> All my water parameters are within
spec, except for the following. I have added a ORP
controller, and calibrated the probe using 400 ReDox fluid, the probe
is in the sump in the same chamber as my return pump. The controller
has been running now for two weeks, I am only able to obtain a ORP
reading of around 212 max. Please note I have not yet
connected the ozonizer. <<When you do...shoot for an ORP of
330-360.>> The tank is low stocked and the water is crystal
clear. Even after a partial water change the ORP has
remained about the same. My pH is also measured by a monitor
and remains constant at around 8.23. The only area with flow
in my sump is at the outlet from my overflow. Would it be ok
to do the following. First use the white wool which I have
at present to trap the incoming dirt, <<Ok...but be sure to
replace weekly.>> under the wool I would place poly filter, and
under the Poly-filter I can place the carbon. <<Should be
fine.>> Also would adding a larger than required skimmer improve
my ORP. <<It could, but likely not significantly.>> Also at
present I am not using any carbon or Poly-filter. Alan <<Regards,
EricR>>

FOWLR Turnover & Circulation
1/18/06 WWM, <One of us> Your site is great -- thank
you. I have been reading it almost every other day for about
2 months now. Think I am now ready to ask some (hopefully intelligent)
Q's. I have a 125g glass tank (18'W x 72'L x
22'H) in the wall - planning a FOWLR. B4 I start
ordering things (want to soon), I have some Q's. My goal
is to keep $$ down w/o tank looking like crap or killing
fish. Here goes: Turnover: Q1) For FOWLR
tank: can I 'get away with' about 8X turnover
(knowing 10X -20X is 'best')? I am thinking of going
with a 1,200 gph capable overflow box, but I'd be limited to 8X if
I go with a less power hungry return pump as below. <Yes>
Details: I have 5.5' from floor to tank top, so I figure
about 6' of head. I am debating return pumps between
OceanRunner 6500 vs. Mag 2400. OR6500 flow is only 1,050 @
6' (8X) but only uses 115 watts (annual cost of $140 for my
area). Mag 2400 pumps a nice 1,700 gph @ 6' (getting me
to 10X max of overflow box after gate valve reduction to the Mag), but
the thing uses 265 watts costing me $315/yr !! <You are wise to
consider energy consumption and cost> Since there's
only a diff. of 2X turnover (unless I add a 2nd OF box w/
Mag 2400) , I'd rather not pay an extra $175/yr if I can get away
with the OR6500 (but don't want to threaten fish or have noticeably
worse water clarity). What to do? Beyond
the 2X difference above, would adding a 2nd OF and getting the full
1,700 gph (taking turnover to 14X) be worth the extra $175/year in
electricity in terms of fish health and/or noticeable water clarity?
(or only if I ever go reef) ? <I would start with the smaller flow
rate pump for now> Circulation Beyond turnover, not sure how
critical circulation is for FOWLR tanks -- seems like a very big deal
for reef tanks. Can I can get away with just the circ.
from the OR6500 return or do I need some add'l in-tank
circ.? <Can be added later...> If so, I'd
probably build a top-of-tank manifold (unless I
can hide powerheads behind my rock which seems likely tough
with a tank only 18' deep). I'd only consider powerheads
because 2 smaller powerheads + OR6500 would still be less wattage than
the Mag 2400. If I go with manifold, I understand I would
clearly need the Mag2400 or higher. <Likely so,
yes> Overflow Q's: Not a reef-ready tank so must use
OF box. Read bad things about CPR losing siphon so will use
a box w/ J tube(s). Q1: I understand that in the event of a
power outage, if sump has enough capacity to hold water draining from
OF box & pipes, and provided return lines have anti-siphon holes,
no flooding should occur in sump (please confirm). <This is a
correct statement> How many, where & how large do the
anti-siphon holes in the return line(s) need to be? <"Over the
top", "inside the tank, just below where you might want to
have your regular water level at its lowest> I thought I read two
1/8'holes on opposite sides of each 1' PVC return pipe about
3/4' below water level but can't find now? <This
is about right> Q2: I understand that if the OF box
siphon has broken, when the power comes back on & return pump
starts, main tank could flood. But, if the water in the return
compartment of a Berlin style sump is only a few gallons because of the
sectional nature of the sump, then is that the max. amount of water
that could come back into tank (probably not enough to flood) since no
more coming from OF box? <Correct... but a pain to deal with such a
small transit volume in terms of keeping the system "topped
off"> Q3: If correct, then is 'worst case'
of siphon breaking: a) potential pump burn out once water in
sump return compartment is gone (does such burnout apply only to
submersibles or externals too?), and b) hassle to restart OF siphon?
<Does apply to both types of pumps... once run more dry, their time
is limited. Not hard to re-start these siphons... top the tank off,
suck away or fill lines and drop...> Q4: Is having two
600 gph OF boxes better than one 1200 GPH? <IMO/E, yes>
If so, why, and I'm confused about something: <In
case one goes, the other may save your pump/s, livestock...> If I
have a 1200 gph return pump and two 600 gph OF boxes, and one OF siphon
breaks but the other keeps working, don't I run the risk of main
tank overflow (since the sump will still be getting 600 GPH from the
working OF but the return pump will be pumping 1200 gph back to tank?)
<Not much... you can/should try this out to determine your maximum
fill mark in your sump...> Isn't this worse than having only 1
OF with a broken siphon (where water flow back to tank is limited to
sump return compartment)? Or, is some equilibrium achieved
at 600 gph due to compartmental design of sump as it only pumps back
what is in the return compartment and this is limited to 600
gph? Would it be a 'jerky' flow (where water flows
into sump return box at 600 gph & gets pumped out at 1200 gph,
leaving the return compartment dry for a few seconds before it fills
again? <Will oscillate a bit, with the pump losing capacity (air
lock around the impeller), catching up and then losing...> Sorry I
am so confused here, but trying to determine if 2 OF's is better
than 1 OF box. Thank you, Paul H. <Thank you for sharing. Bob
Fenner> Siphon Overflows Hello, <<Howdy>> I had a
question about possible flooding with hang on overflow boxes, since I
live on the second floor of an apartment building am a little
concerned. <<And rightly so...>> I have a 75 gal tank with
2 CPR CS90 overflows, a 20 gallon sump, with a MagDrive 7
pump. My question is would it be possible to use an auto top
off device connected to the return pump with the sensor sitting high in
the tank keeping the pump constantly running, if for some reason I had
a siphon break, the sump would then fill the main tank triggering the
float switch, shutting down the return pump and avoiding a
flood. Would this work and if not do you have any other
suggestions for me? <<In theory maybe, but float switches can
fail too. Is good that you have two overflow boxes...do have
a read through our FAQs re: http://www.wetwebmedia.com/ovrfloboxfaq2.htm
>> Thanks a lot for your time, Chris <<Regards,
EricR>> Overflow from a mini-reef 12/14/05 Hi
guys/gals. I'm setting up a small 16 gallon mini-reef
tank to put on my desk and have a question for you. This is
a small bow front tank to which I plan to add overflows. My plan is to
drill dual 1/2 inch holes <RMF would make these a minimum of 3/4
inch> (one in each corner) in the back glass and attach PVC
"Ls" to each with an enlarged fence atop. The
bottom of the tank is tempered or I would drill there. My
question is this: from your experience, does it matter how deep
(distance from the top of the tank to the center of the hole) these
holes are drilled? Obviously, one would want to leave room for the pvc
L and enlarged fence piece, but for aesthetics, I would like the hole
to be as close to the top as possible so you don't see the pipe run
the whole depth of the tank. Or in other words, the pipe
would enter from about 4 inches (or so) below the water surface and
then make a 90 degree up into the larger diameter fence. Is there any
disadvantage to this as opposed to drilling the hole near the bottom of
the back wall with a longer section of pipe between the fence and
L? My other tank is a reef ready 100gal so I didn't have
these problems. <There is no advantage to having a longer pipe just
to bring the water from the surface down to a low-positioned drain
hole. You can drill as close to the top as structural/glass integrity
will allow and your plumbing/elbows will accommodate.> Thanks for
the advice and for all the other help I have gotten from your site
throughout the years. <Always a Peter

Sizing A Weir, Or Baffled by Weirs? -
11/20/05 Hello everybody, hope you are all well.
<<I am, thank you>> My query concerns the building of
an internal weir/weirs on a 4x2x2 tank which will be a reef tank
utilizing a DSB, live rock and refugium for filtration.
<<excellent>> I will also use a skimmer with ozone for
optimum water quality. <<As do I...very good.>> Below
is a picture of the tank and I hope you can see the two x 2"
holes at the top of the back panel (these are the outlets to the
sump) and the four x 1" holes lower down, these are for closed
loop circulation, the main pump/pumps will be in a closet behind
the tank. <<Yep...I see 'em.>> I have searched the
archives for what I'm looking for but just cannot seem to find
what I need, so please accept my apologies for taking up your
valuable time, I hope you can help me. <<I shall give it a
try.>> Exactly how do I build the weir or weirs?
<<Horizontally across the length of the tank and from the
same material as the tank for maximum adhesion.>> I want to
maximize surface skimming so would it be best to build one weir all
the way (or nearly all the way) across the back panel? <<Ah!
(I'm not reading ahead)... Yes it would.>>

Or would it be best to make two separate weirs?
<<Not in my opinion...not most efficient.>> One more
question I cannot seem to find an answer to is just how deep these
weirs should be? <<Deep enough not to "starve" for
water. Since the overflow runs the length of the tank, I think
6"Hx4"D would be sufficient, but don't just take my
word for it, query some of the chat forums (RC, Reefs.org) to see
what has worked for others.>> Do they have to go right to the
bottom of the tank? Or can I make them say 8" deep?
<<Not to the bottom...a few inches as suggested.>> Any
basic mechanical filtration will be at the beginning of the sump so
I can easily switch it out. <<ok>> Would it be best to
build these in glass? <<Yes...to be siliconed in
place.>> And one more question, what should I use to stop the
fish going over the top? <<Of little concern really. Only a
very thin sheet of water (one of the great things about this
design) will be flowing over the top of the weir, this, combined
with correct positioning near the top of the tank will prevent the
fish from going in to the weir. And, the addition of bulkhead
screens inside the weir will help keep any such event from becoming
a tragedy if it were to happen.>> I really am sorry for all
the questions but I value your opinion more than anyone else's
and although I know there is more than one way to skin a cat, I
have become confused with all the advice over here (UK) and you
have helped me more in the past than I could ever thank you for.
<<No worries mate, happy to help. Have a look here for some
additional thoughts on the subject:
http://www.reefcentral.com/forums/showthread.php?s=&threadid=619976
>> Many thanks again. Sincerely Simon (Sorry for the repeat
email but I noticed the pic was lousy and this is a little better)
<<Yes, I chose this one out of the three you sent. Regards,
EricR>>

Reef ready (built in pre-filter) vs. Over-flow box
11/18/05 Hello buddies, <Howdy> I have a 60R 48x15x18 acrylic
tank that I scratched up a bit and I can't remove the scratches and
retain the original luster. Anyway, I was thinking for about $200 I can
get another clear-for-life 60G same dimensions except 2" inch
taller which would give it more volume and larger vertical viewing.
Since the length and width are Identical, I know I can use my stand and
canopy. It's only 2" deeper (20") so my lighting should
still be ok. While I'm at it should I get one with a built in
pre-filter box? What are the pros and cons? (i.e. noise, flooding when
main pump fails, takes up a considerable area of tank, better
circulation of main water to sump, etc, I'm already using
LifeReef's pre-filter box but I could use it in another tank.
Thanks, Anthony <You've about covered the pros/cons... except
there shouldn't be a chance of flooding... I favor this approach
way over over-flow boxes. Bob Fenner>

Overflow 11/9/05 Hello everyone, <Sam in
Malaysia> I have a 4'x1'x1' tank that I would like to
have 2 x 25mm overflows. I thought this would help with the flow of
water since I'm using a 5000L/hr water pump that sucks the water
really fast. <Faster than these overflows/intakes will allow>
Current residents of the tank are 3 tubeworms, 1 yellow tail damsel, 1
fire goby, 1 pink antennae, 1 button polyps, 1 flower pot, 1 star
polyps and Caulerpa macroalgae. I have about 10 kg.s of life rock. Your
help is very much appreciated. Sam Malaysia <... help with
what? You likely need more and/or larger intakes... Bob
Fenner>

Vertical vs. horizontal bulkhead flow-WOW 11/2/05 Hello all
and a pre-question thank you!, <Welcome> Visited a LFS last week,
Pacific Reef in Fountain Valley, Ca. Awesome store. Three 200g reef
tanks displayed, plumbing and all. One SPS, 2 LPS/soft. <Area has
had a history of great stores> The tanks each run with 2 T-4
Velocity return pumps (now called Poseidon's I think) listed at
1250 gph at 4ft of head. They're all 7x2x2, exactly the size
I'm planning for myself. This provides approx. 2200 gph, I think.
The surprise to me, and my question, is that each tank has only 1
overflow box with 1- 1and 1/2 inch hole. Now, he (owner) had to knock
some teeth out of the top of the overflow box to let in the overflow
water. (not at all surprised here, they're only 7x7 inches) BUT,
the 1 and 1/2 inch hole handles the overflow of 2200gallons. The water
level in the overflow box is elevated a bit (about 1-2" ) but the
water volume is not rising, it is handled at that level. <Yes...
from a drain/fitting at the bottom, vertical... actual gallonage moved
not likely more than 1,500 gph> He operates the pumps with 1 inch
intake and outflow, but reduces to 1/2 inch with a 6" LocLine at
the 2-1" bulkheads on each tank to increase velocity. <Make
that 1,000 gph likely> Oh, each T-4 has only one 1" tube up to
a 1" bulkhead. 2 total returns in each tank. 2 pumps up to 2
1" holes. All water flows through a sump. Am I correct that a 1
1/2" hole in bottom of overflow box can handle about 2000gph?????
<Mmm, no... not likely> I saw it with my own eyes, I think. This
is a hole (sorry) lot more than a 1 1/2" hole, id, drilled in the
back of a tank, isn't it? THANK YOU Peter <Would suggest, if
folks are interested, actually testing the flow rate, timed with
buckets of known volume... Bob Fenner>

Re: vertical vs. horizontal bulkhead flow-WOW 11/3/05 Hello
Mr. Fenner and thank you so much for the reply, <Welcome> A
little foggy on this still. Are you saying that only 1000gph is flowing
through that 1 1/2" hole? How possible when the 2 pumps are rated
at 1250 @4'? <Twists, turns, induced drag... am not saying a
specific gallonage BTW, but encouraging you to actually test> Also,
visited Tong's LFS today in same area. Great store, too. <Very
nice stores, folks> I asked the owner, Tan, "how much flow
would a 1 1/2 id hole at the bottom of an overflow box get. He said
2200-2400gph. Aaahh! help! Would you please help me out here? <No
need for help... measure it> Tan also said that a 2" hole would
drain over 3000gph. He said the same hole drilled in back of tank
drains significantly less water. <Yes> Maybe 1/2 as much. He sets
up and plumbs many of the tanks sold there. I know I'm missing
something here, question is where? Is the reduction through the
bulkhead from 1" to 1/2" LocLine the key here? If yes, what
about Tan's numbers? thank you <... a bucket of known volume, a
time piece with seconds measure...> I read your site religiously and
am truly grateful. Thank you for the privilege of corresponding with a
person of your expertise. I will never wash these keys again!!
<Heeeee! Let's not go overboard. Better to have larger fittings
(for flow, noise reduction, safety margin should there be a clog/slow
down in the drainage...). Do please get the simple gear, measure the
actual flow and report back to us. Cheers, Bob Fenner>

Mangrove and bulkhead questions 11/1/05 Hi, I had two quick
questions that I would like to ask your staff. The first one involves
red mangroves. I recently purchased a red mangrove pod from http://garf.org, it did not have the roots or
stems growing yet. I have had this floating in my sump, with a grow
light, and the roots are sprouting very nicely. My question is, at what
point do I remove the pod from the Styrofoam that it is floating in,
and begin to establish a root system? <Yes> I will eventually be
moving this to a 25g tank aside my 125g tank. I wanted to have the tree
elevated on pvc pipes so that the roots are exposed and have lots of
room to spread out, or something of that nature. <Better to
have rooted in a fine substrate...> What methods do you recommend
for something of this nature? <Please read here: http://wetwebmedia.com/mangrovetrees.htm
and the linked files above> My second question is about my overflows
in my 125g. One of my black overflows has a bulkhead built into the
body of the overflow. This bulkhead is approximately 5 or so inches off
of the sand bed. When I turn off my return, there is a slow trickle of
water that continually comes from that overflow. The bulkhead does not
make a secure fit with the walls of the overflow. <Not good> I am
concerned that the power will go out when I am not around, and this
will cause a slow flood in my apartment. <You are right to be
concerned here> I have the bulkhead fitted with pvc pieces and a
cap, so that no water flow goes through the bulkhead, it just seems to
come from around the seal. Do you have any suggestions about how to
stop this bulkhead from leaking? <Yes... requires draining the tank,
drying the area... removing the bulkhead, smearing a bit of Silicone
sealant on the gasket/fitting on both sides (in/out of the tank)...
allowing to cure for a day> The tank is up and running with about
120lbs of LR and 3 fish, so draining it all the way down to silicone
the bulkhead does not sound appealing. <More appealing than the
water on the floor to me> I thank you for all of the help you have
given me so far, and undoubtedly the help your site will give me in the
future. <A pleasure to share. Bob Fenner>

External overflows... some poignant input 10/19/05 I
have read any and all questions regarding external overflows the type
with the j tubes and didn't see any thing about using check
valves to prevent water from spilling out on floors. <...
how would you do this?> I have a 46 gallon bow tank that isn't
drilled. The tank is running two years with no prob. Cant buy a bigger
new drilled tank yet due to a baby on the way very soon. I eventually
will though but in the mean time I have a external overflow I plan to
use along with a ten gallon refugium I made that will go underneath the
display tank. The overflow bulkhead is 1 inch. Which is better for a
return line? 1/2 inch or 3/4 inch ? <... the size of the discharge
on the volute> The pump being used is a Hagen 801 powerhead. I think
it puts out about 800 gallons per hour. My current filter is a canister
which I plan to eliminate when I get this refugium up and running ,puts
out 167 gph. <Where are the spaces between your sentences? What a
waste of time> Can a pvc swing type be used on the return
line? <Yes, but why?> A swing type I guess couldn't be used
on the suction side because it would be mounted vertically and the
check valve would be mounted with the arrow facing downwards rendering
the valve useless. Can normally closed
solenoid valve be used in the return line ?
<... for what purpose/s?> These solenoids are open when there is
power and close when power is interrupted . <Ahh... I would not rely
on this/these... too likely to fail, not re-open, rust...> A spring
type I guess wouldn't work cause the water is gravity fed and the
isn't enough pressure. <Yes> I really want to set up this
refugium now but I'm afraid of finding water on the floor like I
read in some of the postings. The reason I mention check valves is to
keep the water in place and continue flowing once power is
restored without intervention. <I see... but again, I
discourage you doing this...> No water on the floor or my a*% is
grass. Please help me. Any info on how to somewhat foolproof my system
from having water on my floor would be appreciated. Thanks Harry
<Perhaps a large pan, dam around the area... maybe even a drain
within same? Two overflow boxes are better than one... Bob Fenner>
Bulkheads... getting ready to drill, planning plumbing 10/12/05
Hi guys!!!! Like to say it again, great site and info... I am getting
ready to drill my 100 gallon tank at the top. I was wondering will 1
2" bulkhead get me by with enough flow for SPS? <Mmm, I
encourage you to consider two... maybe 1 1/2" ID... better to have
in opposite, upper corners...> I am going to be using a sequence
dart. I guess how much gph will I get with a 2" inch
bulkhead? <Depends on subsequent factors... of plumbing,
turns, water level over...> Or should I drill for 2 2"
bulkheads. <Much better> I just want to get by with one if
possible because it makes me nervous drilling the tank. Also will it be
fine and the same flow if I just have it flow straight to the bulkhead
with a strainer. Or should I put a 90 degree fitting on it with a
strainer inside the tank. Thanks and hope this makes sense.
<Mmm, better to use strainers for sure... and a good idea for you to
check into using "Tees", aspirating the lines after... for
noise reduction, flow... Bob Fenner>

Full length overflow weir question 9/29/05 Hi Anthony,
James & Crew,
The
48x24x24 tank is already built and it has two 2" holes drilled,
one in each corner at the top of the rear panel.<Understand, that is
why I suggested the item in the original query.> It also has four
1" holes drilled across the back panel evenly across and 6"
up from the bottom. These are for closed loop circulation. <Where
will the returns be from the sump? (Hoses overhanging the tank?)>
This will be a reef and small fish tank with live rock as the main
filter, plus remote DSB Plus remote algae refugium. The tank is already
built so I need to find the best way to have the overflow/weir (made of
glass) built? I understood that an end to end overflow would
be best but just how do I go about this? <Why do you feel this would
be the best. Two corner overflows will be very efficient in
a four foot tank.> I hope you can help me as I feel at a loose end
at the moment & am not sure how to make this final part of the
tank. <One thing about designing the tank is that all this should
have been taken into account before the tank was built. The
corner overflows I am referring to below can be cemented in place with
aquarium silastic. It would be very expensive to cut weirs
in a four foot piece of glass to do what you are referring to.> Keep
up the great work. I just wish I had more hours in the day to read up
some more. You guys are just great. Thank you. <You're
welcome. James (Salty Dog)> Simon. Full length
overflow weir question 9/22/05 Hello Crew,
I hope you are all well and remain that way. <Not
bad so far but I've already been on this earth longer than I'm
going to stay.> I spoke to Anthony last time regarding the building
of a tank (48x24x24) and I wanted to build an overflow weir at the back
of the tank to encompass the two 2" holes cut near the top of the
rear glass. I have searched the archives but cannot find the exact
dimensions I need to have this weir built. I would like this weir to be
end to end and would like to ask a couple of question regarding this,
as I have made many mistakes previously and don't wish to do the
same again. You guys have helped me so much in
the past you will never know! Basically I want to know on an end to end
overflow/internal weir (made in glass) how deep should it be and how
far out from the back of the rear wall should it extend? The two drain
holes to the sump are at the top and each end of the tank and are
2" in diameter. I do hope you can advise me as I need this
tank quickly to get some reasonable water flow going.
(that's another story) To all you crew. I just do not know what I
would do without you. <Simon, Simon, Simon. Why on earth
would you want to do that. A full length weir would require
a very large pump to create any usable draw at the weirs to suck in
debris etc. Take a look at this product, it makes more sense
to me. http://www.drsfostersmith.com/product/prod_display.cfm?pcatid=12078&Ntt=overflow&Ntk=All&Ntx=mode+matchallpartial&Np=1&N=2004&Nty=1 You
can contact this company as to whether this will work, but I'm
pretty sure it will.> James (Salty Dog)> Thank you,
Thank you, So much. Sincerely. Simon. 70 gallon plumbing
9/20/05 Hi Bob! Do you think that two 3/4 inch bulkhead
overflows will be enough to handle the output from a 3100 Rio pump that
puts out 900 gal per hour? <Ah, no> Do you have any bad advice
for making a sump out of Rubbermaid containers? <... posted on
WWM... Bob Fenner> Thank you for any input! -Steve Balogh
Overflow, flow, noise... 9/2/05 With a standard
(AGA/Oceanic) one inch overflow (on a 90 gallon tank), would it be
correct that about 300 gph is all that can be run through that (via a
Durso) without the up/down flushing effect? <This is about it>
I've found my Panworld 50PX (590 gph max) has to be ball-valved
back probably about 50% to keep it quiet. Wider diameter
pipe before and after the hole really can't do much here, right
(the Oceanic Durso is already upsized)? <Correct> The only answer
I assume would be to have a larger hole which isn't going to be an
option for me. Still, heavy in-tank circulation can
compensate for this low flow I presume. Frankly, I'm not
sure I'd want a heck of a lot more flow going through the
sump. I appears I'm going to have a hard enough time
quieting the water noise from water crashing into the sump?
<Possibly... there are a few approaches here: http://www.wetwebmedia.com/pbnoisefaqs.htm> Any clever ways
to quiet the water flowing and crashing in the sump, other than say
sinking the drain line and perhaps having a "T" below the
water line in the sump to both smooth out the flow and break the one
flow into many? Like most folks, I'd like to make things
as quite as humanly possible. <I understand...
Please see the link above. Bob Fenner>

3/4 standpipe on a close loop? 8/24/05 I'm setting up a
brand new AGA 75 Bowfront. It came pre-drilled with a 1
1/4" bulkhead and a 3/4" bulkhead (LFS ordered it that
way). The way my LFS originally told me to set it up was use
the 1 1/4 for the standpipe, and the other for the return from my
sump. <Okay> I'm running a Mag 12 in the
sump to the return. It is all working just
fine. However, my X10 controls running the powerheads
for my wavemaker burned out in just a few days! After
reading on here, clearly I believe a wavemaker on powerheads is not the
right way to go. <Agreed> So I've decided to go with a sea
swirl connected to my return line from the sump and set up a couple of
maxi jet power heads in the tank in addition. So here is the question:
I've thought of getting a bigger return pump and hooking up 2 sea
swirls, but I don't think the 1 1/4" has enough flow rate to
take advantage of a larger return pump. <Also agreed>
Am I crazy to think of taking my 3/4" bulkhead and
using that hole as a 3/4 stockman standpipe (I have space for a
stockman but not a Durso design)? <Won't get
you much more... think of the mathematical formula for the surface area
of a circle... pi R squared...> The other alternative is to use the
3/4" as a downspout to a separate smaller pump and set up a close
loop with an extra Mag 7 I have and leave the flow to the sump alone.
<A better idea> In that case I would connect the
smaller pump to a 1/2 sea swirl and the sump return to a 3/4.
<Sounds good> Of course the final option would be to drain the
main tank and then take male and female brushings and create a 1 inch
"bulkhead" which would fit in the pre drilled
hole. However, I worry that this would not be a sound
construction. <Me too> (I have looked for larger bulkheads that
would fit in the pre-drilled hole, but can't find any, the hole is
just too small). <Bingo! Yes> Any thoughts would be greatly
appreciated. <Your proposed changes are good... that or re-drilling
the tank are your easiest options. Bob Fenner>

Re: 3/4 standpipe on a close loop? Bulkhead f'
8/25/05 Thanks, you all are great! It is always
difficult to guess on these things and I know once I set it up is much
harder to change. One quick update: Decided to do the close
loop approach. By chance I did find a Schedule 80 threaded
coupling where the threads fit in the 1.5" pre-drilled hole but
because it is schedule 80 the outer lip is larger then the hole, in
fact about the same size as the gasket. I have read of some
people using threaded fittings in this manner as the bulkhead. Should I
be really worried or is this a safe approach? <Can
be safe... with securing the bulkhead first... with a smear of
Silicone... letting set-up for a day or more... and gingerly (so as not
to tear the Silicone) threading a fitting over the outside
thread...> Of course the sane thing to do would be to just use the
3/4 bulkhead, but I'm just not happy with the idea of such a small
overflow. <Me neither... you would be disappointed I
assure you> I still have a few days before I have to make a final
decision (wife is tired of the room where it is being constructed is a
mess). Thanks again. <Welcome. Bob Fenner>

Tank flow from Overflow ... not so "reef-ready" tanks
8/11/05 Ok I have read all over your site about micro bubbles and
problems of the such, but my problem isn't exactly in that reading
and I don't know where else to turn. I have an Oceanic
75 gal with built in overflow and oceanic overflow kit. The
line to the 38 gal sump is 1" tubing <Too small...> that
goes directly into the compartment that contains the skimmer (ASM
G1). There are three baffles, which flow into a refugium and
then finally over one last baffle to the return pump (a Mag 9.5) that
returns the water through a 3/4" line with a ball valve and then
to a T joint to both corners of the tank. I cannot get a
steady flow of water through the line to the sump. It
constantly takes in a lot of water mixed with small air bubbles and at
times very large air bubbles. <... yes> I called the LFS and they
said I should be getting a steady flow through my overflow to my sump
with the setup I have with or without the ball valve. <... no> I
have tried to move the standpipe up and down, add a small piece of air
line tubing 3/4 the way down to the sump, and play with the ball valve.
<... won't work> None of these have worked and I am out of
answers. Is this a common problem or are there any solutions
that I am not using. Thanks Erik <Is a very common problem... with
most all so-called "reef ready" tanks/kits... the
through-puts (holes...) are too small and too few... You need a larger
drain line... practically speaking 1 1/2 or two inch inside diameter...
two would be better than one... Yes... requiring draining the tank...
Please read here: http://www.wetwebmedia.com/overfloboxfaqs.htm and the linked
files (till you understand) above. Bob Fenner>

Re: Tank flow from Overflow 8/12/05 Quick follow-up.... If I
used the 1" and 3/4" holes in the overflow to feed water into
the sump and created a new return line should that do the trick (see
below) as far as getting water into the sump at a better
rate. Instead of drilling new holes or making the current
holes larger. Erik <Might accommodate adequate flow, would still be
noisy... Bob Fenner>

Flow question part 2 8/9/05 OK, sounds good. I
will convert all of the bulkhead holes to drains, my question now is
what size pipe do I use for the standpipe? For the 1"
bulkhead I used 1.25" PVC for the standpipe, for the 3/4"
bulkhead would I make a standpipe from 1" pipe or 1.25" pipe
just like I did for the 1" bulkhead? D'Wayne <Any size that
is at least the same size as the bulkhead should do. The
only downside to upsizing is that objects (like snails!) could easily
fit into the standpipe, but also easily clog the
bulkhead. Extracting them could be
difficult. Since your standpipes should be protected anyway,
this is a minor issue. Best Regards. AdamC.>
Drilling Bulkheads - 08/06/05 Dear WWM Crew, I have decided to
get my 30 gallon pre-reef tank drilled and just skip messing with
siphon overflows. (Thanks to reading about all the lovely
problems) <<Excellent! You'll be much happier for
it mate.>> But I had a few questions. <<ok>> First I
gathered that tempered glass cannot be drilled but I don't know if
my tank is tempered or not. It is an All-Glass 30 gallon
long model (36x12x16) as far as I can gather from the previous owner it
was bought new in the mid 90s. Would you think that this
tanks back wall would be tempered? <<My experience with All-Glass
has been that if any, only the bottom pane was/is
tempered. But it's easy enough to contact the company
and ask them about this one re the date of
manufacture. I've drilled a few of their tanks (through
the sides), both recent and unknown manufacture with no problems (if it
is tempered you'll know in a hurry when it "blows out"
and scares the bejesus outta ya <G>). Tanks of recent
manufacture should/will be marked if tempered...but then that
doesn't help you...>> If not, I am planning on having (2) 1
3/4" holes drilled to accommodate (2) 1"
bulkheads. I want to have one to each side of the tank and
have one drain tee off to a plenum and then connect to the other to
feed the sump. I believe that they should be a minimum of
3" from the top of the tank and 3" from each
side. Is this correct? <<I just did this very thing
for one of my club members...when drilling bulkheads near the edge I
recommend placing the outer edge of the holes equidistant from the edge
at a distance equal to the diameter of the hole...e.g. - 1 3/4"
hole - 1 3/4" spacing, 2 1/2" hole - 2 1/2" spacing,
etc... This will let you get and still maintain
strength/integrity of the pane, without guessing at it.>> I am
planning on having between 600-700gph return at first but decided on
the larger bulkheads in case I want/need more. Does this
sound okay so far? <<Problems here I think. Be
cautious of the flow calculators...better to talk to folks/query as
you've done here. The reality is a 1" bulkhead will
perform safer, quieter, and with less aggravation/constant fiddling of
the plumbing if you only try to push about 300-350 gph per
bulkhead. So...your already maxed out in my
opinion. You'll need to go to a larger bulkhead if you
want to turn more water.>> The tank is for 2 True Percula clowns,
Euphyllia glabrescens, Plerogyra sp., Lobophyllia sp., and maybe a
Fungia repanda. <<Ahh...so nice to see you're not going for
the usual "reef garden" mix of organisms; you'll be all
the more successful for it>> Is the flow above reasonable for
these species? <<Yes...be sure to diffuse/spread throughout the
tank via multiple outlets.>> If you have any other thoughts or
suggestions please do not hesitate to tell me. <<Already have
<G> >> I would rather know now if this setup
would work than after I set it up. :) Best regards,
Andrew <<And to
you in kind, EricR>>

Re: Drilling Bulkheads - 08/06/05 Dear Eric,
<<Andrew>> Thanks a lot for your advice, I'll heed it
as WWM usually saves me from my own worst ideas. But I had a
few thoughts to run by you. <<Alrighty>> If I switched out
the 1" bulkheads for some 1.5" bulkheads would this fix my
problem of over pumping? Or, could I make one of the
bulkheads a 2" and leave the other as a 1" (the one that tees
off to the plenum) and instead of connecting them just run both lines
to the sump? <<A pair of 1 1/2" bulkheads should be
fine. The 1" bulkheads would work, you would just need
to size/regulate your return pump (maybe plumb in a gate-valve on the
return side) appropriately. Please have a look through our
plumbing FAQs for more on this: http://www.wetwebmedia.com/plumbingmarart.htm>> Also,
I'm not drilling the tank myself but from what you said it is
possible to do it yourself? <<Yes, with the right
tools/application.>> Or would you have a glass company do
it? I have never done it before so I don't know if I
want to chance it. <<First time for everything
<G>. But if you're truly uncomfortable/not handy,
it might be best to fine/pay someone else to do it for you.>> I
think that's everything. Thanks again, Andrew <<Most welcome,
EricR>>

Bulkheads And Flow - 08/07/05 Dear Eric, I promise this is
the last time I'll bother you. <<Hello again Andrew...no
bother...really...I'm happy to try to assist.>> But I was
thinking about it and thought that (2) 1.5" bulkheads would/could
give me around 1000gph. (Please correct me if I'm wrong) <<If
you're talking about both draining to the sump, then yes, is quite
plausible. Though I must say, that is an awful lot of water
to process through a sump on such a small tank (30g)...the slightest
restriction is going to put water on the floor in a
hurry. Not to mention the NOISE it is going to
make. I would recommend using one bulkhead to drain to the
sump in conjunction with a smaller pump (say a MAG 5), and use the
other bulkhead to feed a closed-loop with another MAG 5 or even a MAG
7.>> I was planning on running a Mag Drive MD9.5. I
calculated that this would give me about 800gph at 4.5'
head. Is that to much to run through a sump? <<Ah,
should read ahead <G>...>> I wasn't planning on having
a large sump, maybe 10-20 gallons and a separate 10 gallon
Plenum. I was planning on running the return into a manifold
and was wondering if I should stick with the 1" bulkheads and run
a smaller pump and drill a third 1" bulkhead to run closed
loop. I would only do this if I had no other choice about
the sump. <<Now you're talkin'... Here's
my recommendation for the simplest, most manageable configuration in my
opinion. Have three holes drilled for 1"
bulkheads...Use two bulkheads to drain to the sump with a MAG 7 return
pump. Use the third bulkhead to feed a closed loop with
another MAG 7 pump. With head loss due to height/plumbing,
you'll have a total flow rate of around 600-700 gph I'm
guessing. By using "two" 1" overflows you
will be able to increase the pump size a bit (MAG 9.5) if you determine
you need/want the extra flow. Also...if given the
choice...go with the 20 gallon tank for your sump...you need to ensure
you will have enough "empty space" to handle the drain-down
from the display tank in the advent of a power outage.>> It will
only contain a skimmer, a little mechanical filtration, and a little
chemical. <<and your pumps>> Will
this be overloaded? <<Assuming you go with the larger of the two
sump choices (20g), should be fine.>> Thanks Again (and again and
again...) Andrew <<My pleasure my friend, EricR>>